ANDROID: Kbuild, LLVMLinux: allow overriding clang target triple
Android has an unusual setup where the kernel needs to target
[arch]-linux-gnu to avoid Android userspace-specific flags and
optimizations, but AOSP doesn't ship a matching binutils.
Add a new variable CLANG_TRIPLE which can override the "-target" triple
used to compile the kernel, while using a different CROSS_COMPILE to
pick the binutils/gcc installation. For Android you'd do something
like:
export CLANG_TRIPLE=aarch64-linux-gnu-
export CROSS_COMPILE=aarch64-linux-android-
If you don't need something like this, leave CLANG_TRIPLE unset and it
will default to CROSS_COMPILE.
Change-Id: I85d63599c6ab8ed458071cdf9197d85b1f7f150b
Signed-off-by: Greg Hackmann <ghackmann@google.com>
[astrachan: Added a script to check for incorrectly falling back to the
default when CLANG_TRIPLE is unset]
Bug: 118442619
Signed-off-by: Alistair Strachan <astrachan@google.com>
diff --git a/scripts/clang-android.sh b/scripts/clang-android.sh
new file mode 100755
index 0000000..9186c4f
--- /dev/null
+++ b/scripts/clang-android.sh
@@ -0,0 +1,4 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+
+$* -dM -E - </dev/null 2>&1 | grep -q __ANDROID__ && echo "y"